We may grow old because we don't get cancer.

January 2, 2002 11:30 PM

We may grow old because we don't get cancer. Researchers have identified a gene called p53 whose function is to minimize tumors, but it may also cause aging as a side effect.
posted by Steven Den Beste (14 comments total)

"But mice and humans are close evolutionary relatives,"

I thought man and monkeys are [assumed to be]. When did mice got into the equation? Must be the whole GENE thing and not the whole Darwin thing [if you knowwhat I mean].

"Even though virtually none of them came down with cancers, they died, on average, at 96 weeks, compared with 118 weeks for normal mice. Their enhanced cancer resistance was accompanied, in other words, by a 20 percent drop in life span."

I look forward for the day when human are used to do experiment so mice can live a better life.
posted by cqny at 2:11 AM on January 3, 2002

It's all relative, cqny. All mammals on earth are close evolutionary relatives of all other mammals. They say man and chimp share ninety-eight percent of their genetic make-up, but, if I remember correctly, all mammals share ninety-four percent.

I'm not sure how related the two areas of research are, but there is another possible inverse link between aging and cancer that has been around for a while. Telomere chains, which are basically the EOF for DNA shorten each time a cell divides. When it's all gone, the cell stops dividing, and eventually most of our cells will run out. It is hypothesized that this end of cell division is one of the causes of aging. Scientists know that they can extend cell replication by adding telomeres, and possibly extend life. The catch? The ability to regrow telomeres one of the things distinguishes a cancer cell from a normal cell.
posted by Nothing at 3:08 AM on January 3, 2002

More on telomere theory and research in this article titled "Human Immortality: A Scientific Reality? from The Daily Grail.

If you're alive in 20 years, you may be able to live forever.
posted by ferris at 6:20 AM on January 3, 2002

Must be the whole GENE thing and not the whole Darwin thing [if you knowwhat I mean

No. Care to elaborate?

I look forward for the day when human are used to do experiment so mice can live a better life

Oh, nevermind.
posted by whuppy at 6:36 AM on January 3, 2002

Yes, chimps are closer to humans than mice, but in the time you can do a genetic experiment on one generation of chimps, you could have done tens of generations of mice. Plus mice are cheaper, which is really important when you consider the kind of scaling-up necessary in genetic studies. The mouse is a model organism, just like fruit flies, roundworms, and E.coli. There's no one-to-one correlation between mouse and human, but there's been a remarkable track record of similarity.
posted by whuppy at 6:40 AM on January 3, 2002

Whatever. I'd rather grow old than get cancer.
posted by Domain Master 666 at 7:14 AM on January 3, 2002

I'd rather live forever, never growing old or getting cancer.
And I'd like lightning to shoot out of my fingers. And I'd like to make people's heads explode telepathically.
And a pony. I'd really like a pony and I promise I'll take good care of it.
posted by whuppy at 7:23 AM on January 3, 2002

You can also easily make "knockout mice" -- mice missing one specific piece of gene code. Knockout mice simulate the effect of human "single nucleotide polymorphisms" (SNPs), and enable the researcher rapidly to test a variety of therapies for the illnesses caused by the SNP in question. (SNPs are believed to be at the root of many intractable human ailments.)
posted by MattD at 7:44 AM on January 3, 2002

Whenever Steven Den Beste posts to MeFi, be sure to check website for more in depth commentary.
posted by whuppy at 8:05 AM on January 3, 2002

There was a show on the Discovery Channel that covered p53. New Hope: Breakthroughs, I think.

P53 Mutation Java applet
The mouse in science
posted by samsara at 8:19 AM on January 3, 2002

Thanks whuppy - I hadn't really been interested in the post until I read his commentary.
posted by revbrian at 9:41 AM on January 3, 2002

A few clarifications: p53 is a protein, not a gene. (Like all proteins, it is encoded by a gene, but the gene is not the protein.)

p53 has not just been identified--in fact, p53 was named "Molecule of the Year" by Science in 1993. The article is reporting new discoveries about p53, but p53 itself is not new.
posted by DevilsAdvocate at 9:43 AM on January 3, 2002

Actually there is a p53 protein and gene.
posted by samsara at 10:23 AM on January 3, 2002

This is fascinating, but I didn't really understand the explanation for why both sides of the coin tend to show up at once - it seemed more like the passage of time just allowed for more mutations which meant a greater likelihood of p53 failing and also of cells not reproducing.

Or wait, is it essentially that all of life is a fight against cancer, and eventually the body ages itself in this fight, which makes it more likely that it will lose... okay, I guess that makes sense.

sorry 'bout talking to myself. Hope that was useful for someone else too.
posted by mdn at 3:18 PM on January 3, 2002